Disk drives typically include a disk clamp that provides a disk clamping force for holding one or more disks to a hub. Thus, disk clamping is becoming more and more important not only for regular Hard Disk Drives (HDD) performance but also under extreme conditions such as operational shock and non-operational shock. A reliable clamping force may maintain the integration of the whole disk pack, preventing the disk from separating or sliding under shock event.
FIGS. 1A and 1B show perspective and cross-sectional views of a related clamp 140 that could be used to provide clamping force. The clamp 140 has an annular shape and one or more threads 142 formed on a radially interior region 144 of the clamp. As shown in FIG. 1B, the clamp 140 also has a flat upper surface 146.
Further, to reduce data streaming issues and vibrations during operation imbalances of the disk pack must be within certain imbalance tolerances. In order to correct or compensate for imbalance in the disk pack, plugs or wire pieces various size or shape may be inserted into holes provided in the disk hub to correct the mass distribution of the disk pack.
However, with decreasing form factors and tighter imbalance correction specifications, the effectiveness of using plugs or wire pieces inserted into holes provided in the disk hub to correct imbalance of the whole disk pack has been reduced.
There is therefore a need for an improved disk clamp design and imbalance correction method.